Shaking its tail feathers, or at least having them, may have kept a new species of winged dinosaur from crash landings. The creature, called Changyuraptor yangi, had tail feathers nearly 30 centimeters long, roughly 30 percent of the length of its skeleton, researchers report July 15 in Nature Communications.

Fossils of C. yangi, a relative of the the Velociraptor and other raptors, show it also had feathered legs, giving it a four-winged look. The creature appears to have been the largest the...